package org.apache.lucene.demo;

/**
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
//import org.apache.lucene.index.Term;

/** Deletes documents from an index that do not contain a term. */
public class DeleteFiles {

    private DeleteFiles() {
    } // singleton

    /** Deletes documents from an index that do not contain a term. */
    public static void main(String[] args) {
        String usage = "java org.apache.lucene.demo.DeleteFiles <unique_term>";
        if (args.length == 0) {
            System.err.println("Usage: " + usage);
            System.exit(1);
        }
        try {
            Directory directory = FSDirectory.getDirectory("index", false);
            IndexReader reader = IndexReader.open(directory);

            Term term = new Term("path", args[0]);
            int deleted = reader.delete(term);
       
            System.out.println("deleted " + deleted + " documents containing " + term);

            // one can also delete documents by their internal id:
            /*
            for (int i = 0; i < reader.maxDoc(); i++) {
              System.out.println("Deleting document with id " + i);
              reader.delete(i);
            }*/

            reader.close();
            directory.close();

        } catch (Exception e) {
            System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage());
        }
    }
}
